IMAGE SENSING DEVICE

摘要

PROBLEM TO BE SOLVED: To suppress the saturation of a signal level and to obtain a better linearity by providing over flow drains(OFDs) and over flow gate(OFG) switches on a CCD image sensing device. SOLUTION: A push-broom scanning sensing apparatus 1 which is mounted on an artificial satellite for example, scans the surface of the ground, and obtains two-dimensional picture images, is provided with OFDs 9 which correspond to each line of photoelectric converting elements 1 and discharge signal charges from the photoelectric elements 1 outside without transferring them to CCDs 2, and OFG switches 10 which transfer the signal charges from the photoelectric elements 1 to the OFDs 9. And a signal light forms an image on a CCD image sensing element 11 by an optical system 5, and the image of a target moves on the CCD element 11 in accordance with the movement of the apparatus. The photoelectric elements 1 are exposed while the target image moves one pitch, and within that exposed time the OFG switches 10 operate in accordance with a set time by an OFG switch driver 12, and generated charges are discharged to the OFDs 9 during that time.